There are currently various special devices for respirating patients, which are optimized for the particular task. The most important prior-art embodiments are portable respirators, intensive respirators and anesthesia devices with rebreathing systems.
Depending on the particular situation, it is therefore necessary during mechanical respiration for the patient to be separated or disconnected from one device and connected to another device. This operation requires a separation either between the tube or mask, and the breathing tube system on the patient side of that system, or between the device and the breathing tube system on the device side of that system. Mechanical respiration is interrupted in both cases and there always is a loss of pressure in the lungs. The operation is critical, and the loss of pressure leads to collapse of the lungs and hence to a worsening of the patient's condition in the case of many patients who require mechanical respiration.
In addition, respiration is not being monitored by means of pressure sensors during the changeover time. If the changeover operation takes longer, manual respiration is, moreover, necessary by means of a manual breathing bag. For example, the following changeover scenarios with transporting of a patient and corresponding changeovers of the respirators are possible or necessary during a hospitalization:                Emergency department/intensive care unit;        Emergency department/surgical area/intensive care unit;        Changeover between intensive care unit and various diagnostic environments, such as computed tomography (CT) or nuclear spin tomography (NMR);        Changeover between intensive care unit and surgical area; and        Changeover in the surgical area from the preparation for the surgery via the surgery to the recovery area.        
There is a need for frequent transportation with the more or less painful and unpleasant changeovers from one device to another and reconnection operations associated therewith especially in case of severely ill patients because of the differential diagnostic examinations to be performed in stationary special installations such as CT, NMR or in the cardiac catheterization laboratory.